Electric light



C. J. SCHROEDER ELECTRIC LIGHT Deco 4, K928 I Lwsmz Filed Nov. 22, 1926 Patented Dec. 4, l928.

UNHTED stares CHARLES J. sonnonnna, 'or'mrnonn, rumors.

ELECTRIC LIGHT.

- Application filed November 22, v1926. Serial No. 150.061.

This invention relates to electric lamps and particularly to a lamp adapted for use in automobile headlights.

It is an object of this invention to provlde an electric lamp for use in automobile headlights employing parabolic refiectors having a primary and secondary e1ectrically energizable lighting filaments in which a shleld is provided for the secondary filament having a top side, front and rear walls, for preventing projection of the light upwardly from the filament and permitting the lights to be projected downwardly and inclined in relation forwardly and sideways to a limited extent,

but not rearwardly through the articular association of the shield with the ament so that, the back wall lies substantially adjacent the filament.

The invention comprehends numerous other objects residing in the specific construction of the shield and its association in a particular manner with one of the filaments of an electric bulb so that light from the filaments can only be projected into a small sector of the forward lower portion of a parabolic reflector in which the lamp is placed for preventing the light from shining on the back and upper sections of the reflector and thereby prevent glare in the eyes of an apeo proaching driver, yet providing suficient illumination on the roadway in front of the vehicle equipped with the lamp so that it may be operated without dificulty.

In the drawing forming part of this application Figure 1 is a longitudinal sectional view through a portion of a headlight showing the same equipped with the electric lam of this invention, other portions of the headhght being shown inside elevation.

Fig. 2'is an enlarged detail view of the lamp showing the container and shield in longitudinal section.

Fig. 3 is a sectional View taken on the line 33 of Fig. 2.

1 indicates the improved electric bulb forming the subject matter of this invention which includes a translucent evacuated container 2 of usual construction mounted in the base 3 no at the rear end, where it is provided with the stem at also of usual construction, which receives and through which passes the conductors for the filaments and also the sup-- porting wires therefor. A primary electri- E cally energizable filament is indicated at 5 which is supported on the wires 6 carried by stem a which also form conductors for the current, while a secondary filament is indicated at 7 having the opposite ends attached to the wires 8 also supporting and forming conductors for the current to energize this filament, independently of the filament 5.

It is to be noted that these wires 8 are formed with hook-shaped ends as indicated at 9 so that the filament 7 is supported above the longitudinal plane of the wires 8. A rod member 10 is mounted in the stem a and extends outwardly in substantial alinement with the filament 7 to the end portion of which is attached the rear wall 11 of the shield member 12. lhis shield member in addition to the rear wall 11, has an elongated top wall 13 from the opposite side of which depends a side wall it and at the forward end is provided with the front wall 15, the lower end portion of which extends below the lower edges of the rear and side walls as clearly illustrated in Fig. 2.

This shield member 12 is so mounted on the rod 10 and supported thereby within the container 1, that the rear wall it is in close proximity to the filament 7 as clearly illustrated in Fig.2, while the rear portion of the top wall 13 is also in close proximity thereto. In this way, the lower edges of the side walls, the front wall, and the rear wall extend and terminate in a horizontal plane substantially below that of the filament, and prevent any li ht from the filament from being projects upwardl above the horizontal plane, and in ad"tiononly permit light projected in a substantially downward direction from the secondary filament 7 This is particularly true with respect to the rear wall which in close proximity to the filament, permits only rays to beprojected downwardl therefrom and prevents rays of light from eing projected rearwardly. The extent of this shielding oil-the filament 7 by the rear wall ll'is indicated generally by i the dotted line 16 in Fig. 2, while a substantial amount oflight may be projected forwardly from the filament 7 from the "forwardly and downwardly extending plane of the dotted lines shown at 17 in Fig. 52.

The dotted lines 18 in Fig. 3, clearly illusreflector 19 as indicated by the dotted lines 20 in Fig. 1, While no light will be permitted to project on the rear portionor the upper portion of said parabolic reflector.

It has been found from practical experience that the glare from motor vehicle headlights particularly those usingtwo filament bulbs, is due principally to the light reflected from the upper portion ofthe parabolic reflector and principally to that projected from the back portion thereof, and this invention is designed to shield the light from-the secondary filament from the entire upper segment of the reflector as well as the back portion thru the provision of the side and rear walls located closely adjacent to the filament and having the lower edges extending substantially below the horizontal plane thereof,

' while the front wall preventsthe light from the filament from shining forwardly above the horizontal plane of the filament, but permits a" substantial amount of light shining forwardly to be projected downwarddirect ly onto the surface of the roadway in advance ofthe vehicle equipped with the bulb.

It is particularly important therefore, in connection with this invention, that the shield be positioned in a special manner relative to the secondary filament, thatv is, with the rear wall in close proximity to the filament, and the side and rear walls depending substantially below the horizontal plane thereof as clearly shown in Figs. 2 and 3, for limiting the light projection onto the'reflector to a substantially small portion of the forward lower part thereof.

Havin thus described my invention, What I claim as new is I A reflector for electric lamps comprising a substantiallyrectangular shaped relatively elongated cover including a longitudinally extending top, a forwardly inclined front wall and vertical rear and side walls, said cover being open-at its side opposite from said top and a light filament disposed there'- within, said front'wall extending downward- 1y beyond the .edges of the side walls and constituting a light deflector for the filament whereby to direct the rays thereof at an inciined angle from the horizontal plane there- 0 In testimony whereof I afix my signature.

crannies J. scnnonnnn. 

